Does my dog or cat need to get a tetanus shot?

One of my blog readers shared last week that her daughter’s dog was recently diagnosed with tetanus and is undergoing treatment. Poor doggie! I am fervently hoping that her dog responds and will have a complete recovery! She asked if I could write about tetanus and shed some light on this infection in pets. In truth, I think we are much more aware of tetanus in ourselves than in our pets. We all know that we are supposed to get a tetanus shot at least once every 10 years, and if we get poked in the foot by a rusty nail, we need to get a booster shot. What’s the deal with this infection?

Tetanus is caused by a bacterium called Clostridium tetani. This organism is a dirty bugger. Really, it lives in the dirt. So when we step on a rusty nail, or cut our hand on an old tin can, there’s a good chance that C. tetani is there, contaminating our wounds. It happily grows in that wound, and it isn’t the infection itself that causes the problem. Rather, it’s the fact that C. tetani produces a toxin called tetanospasmin that acts on the nervous system, causing muscle spasms, contraction, and rigidity. The term “lock-jaw” refers to rigid muscles in the neck and cheek areas that prevent a person or animal from fully opening the mouth.

This toxin is really powerful. The minimum human lethal dose is around 175 nanograms in a 150-pound person. One nanogram is one-billionth of a gram. One gram is roughly the weight of a dime. So we’re talking about splitting a dime into a billion pieces, and 175 of those pieces is enough toxin to take down an adult person. Yikes. I personally am really glad we have a effective an vaccine to prevent this painful and potentially deadly disease.

It turns out that humans (and horses and livestock) are more sensitive to the effects of tetanospasmin than are cats, which are quite resistant. Dogs have intermediate sensitivity. Horse owners are used to vaccinating for tetanus, as it is considered a core vaccine for all horses. We don’t routinely vaccinate our pets for tetanus, though. This doesn’t mean they can’t get it, it’s just pretty uncommon.

When a dog develops tetanus, often it starts as the localized form. This means perhaps only the foot or one leg has muscle spasms and rigidity, and typically this occurs in the area of the wound and site of infection. The localized form can develop into the generalized form, and the dog’s ears will be pinned, brow furrowed, lips pulled back. Seizures can occur, and the dog may have trouble breathing.

Treatment includes antibiotics to kill the C. tetani in the wound, anti-toxin to neutralize tetanospasmin that hasn’t already bound to the nerves, and muscle relaxants and anti-seizure medications. These animals are very sensitive to light, loud noises, and other stimuli, so it’s important to keep them in a dark and quiet place while they are in treatment. A dog with tetanus may also need help eating and drinking. It may take a week and as long as a month for full recovery.

I want to thank Gail for sending me this topic idea. I hope you learned something, and if you have topic ideas, please share them!

We were out of state and a friend was watching our dog. She had blood on her paws and mouth three days ago but they couldn’t find a cut or anything. She hasn’t gotten up or really even eaten much since then. We got home late last night and her legs are all stiff, eyes glasses over, difficulty breathing and grows and barks at us when we go near her. Does that sound like tetanus, and what should I do? Little Leary about trying to move her or take her somewhere, when she’s in so much pain, and not herself, and growling and barking when I get hear.

I have two questions. I just started researching tetanus in cats when I found my 1 yr old cat playing with, attacking and chewing on a RUSTY screw in our new back yard today. As soon as i saw it, i told her to never do it again, and opened her mouth to look for wounds. The gums around two teeth were minorly red and irritated and slightly bloody (as if with gingivitis). I looked again 8 hours later and the redness is gone. Well, now that i see the lists of symptoms, i see that she has had some of these ever since getting her rabies vaccine in april. The grinning appearance, furrowed brow, excessive drooling (but only when eating–she leaves the plates soaked, unlike my other 3), and spasms in her hind legs (which can never be repeated in front of the vet because she’s already shaking with fear). I do have video, but a vet (whom i dont like) said it looks like she’s sleeping. I havent yet found a vet i 100% trust in our new neighborhood. No, she is not sleeping when it happens. So my questions are: 1) should my girl get any antibiotics just from exposure to this nail? And 2) is it possible to have tetanus for months without it going away or progressing into the most horrible form? She eats fine (although she does not eat dry or crunchy food).
thanks!

Hello…you pose interesting questions. Out of an abundance of caution, antibiotics may be warranted following her chewing on the rusty screw. I think the chances of her contracting tetanus from this exposure are low, in part because cats and dogs are more resistant to tetanus. However, if antibiotics are used early enough, it can prevent tetanus. Secondly, while I do believe your description of the symptoms your cat has had since April, it’s hard for me to understand how she could be showing symptoms of tetanus for that long without having more severe (and life-threatening) symptoms. In other words, the disease would usually progress. I am wondering if instead this could be related to the rabies vaccination, a condition known as vaccinosis. You can read about this condition here. Where are you located? Can you find a holistic veterinarian at this site who is close to where you live? I think this would be your best chance to help your cat get past what is going on. I hope this helps, let me know how you make out! -Dr. Carney

I just read about the pup with tetanus and feel for you. We just lost our 9 yr old English springer spaniel who was also my husbands companion and who also has MS. It has been over 3 years since this vet has seen tetanus and has has never seen it in our area. I’m thankful our vet was able to recognize the disease, but it was too advanced at her age.

Hi April – I am so sorry to hear about your loss. It’s heartbreaking when we lose our pets for any reason, but especially so in this case where your vet correctly diagnosed tetanus but treatment was unsuccessful. I think we could easily create a tetanus vaccine for dogs, but there just isn’t a market for it because it happens so infrequently in dogs. Hugs to you and your family…Dr. Carney

Our 7 month old Cocker Spaniel just died of tetanus. The death was 8 days after a spay by a vet. 5 days after the spay, Molly started acting sick and presenting with some spasms. On the 6th day, she didn’t want to walk and we got her back to the vet. Her jaws were “locked.” He said she was just having some pain, ran a few tests and x-rays and sent us home with pain pills. She declined that night. Day 7, Molly was stiff and very ill. We took her to an emergency clinic. Again, they told us she was having pain. Later that day we took her back to the emergency clinic. They put her in ICU. She was as stiff as a rocking horse. We got a call in the middle of the night from the Dr. of Internal Medicine. She told us it was likely tetanus. Finally, someone recognized the symptoms, but it was too late. Molly had fevers that spiked at nearly 106 and so much damage had been done that we chose to put her down. I think this should have been caught earlier by the vet, and Molly could have possibly been saved. It was a horrible death, and we miss Molly each day of our lives. My wife has MS, and Molly was her companion dog. She was extremely special to us.

Dear Blake – I am so very sorry to hear about your Molly’s illness and passing. My heart hurts for your family. I can’t speak to why the doctors caring for Molly didn’t pick up on her symptoms earlier, when treatment might have been successful. I want to thank you for sharing your story here, because it may help someone else’s dog avoid the same pain and suffering Molly experienced. Hugs to all of you – Dr. Carney